text: Cobalt is essential for most higher forms of life, but more than a few milligrams each day is harmful.  Although poisonings have rarely resulted from cobalt compounds, their chronic ingestion has caused serious health problems at doses far less than the lethal dose. In 1966, the addition of cobalt compounds to stabilize beer foam in Canada led to a peculiar form of toxin-induced cardiomyopathy, which came to be known as beer drinkers cardiomyopathy'.
  Furthermore, cobalt(II) chloride is suspected of causing cancer (i.e., possibly carcinogenic, IARC Group 2B) as per the International Agency for Research on Cancer (IARC) Monographs.
  In 2005–06, cobalt chloride was the eighth-most-prevalent allergen in patch tests (8.4%).